1. Field of the Invention
The invention relates to a receptacle, for irregular shaped pieces of rock, having passageways therethrough so that one layer of black surfaced rock may be exposed to sun rays at times when such rays are available as a source of heat and the balance of the rocks function in the combination collector and heat storage unit.
2. Prior Art
Collectors of heat from solar rays are old but not as a part of a combination collector and heat storage unit. The present combination of rock layers with rocks of irregular shapes, providing air passages through the rock layers and with some thereof exposed to the sun's rays, all in combination with air circulation and in combination with the air flowing in a hot air furnace appears to be absent in the prior art.